Lavatory unit

ABSTRACT

Lavatories on-board a vehicle, and in particular to a lavatory unit for use by persons with reduced mobility on-board a vehicle are described. The lavatory unit includes a lavatory housing structure enclosing a lavatory interior space, a door opening in the lavatory housing structure, a toilet assembly inside the lavatory interior space, and a transition seating support for a user. The transition seating support provides a first transfer position and a second transfer position. In the first transfer position, in an open door state the transition seating support is directly accessible for a person sitting in a wheelchair that is located at least partly outside the lavatory unit such that the person can transfer to the transition seating support and vice versa, and in the second transfer position, a person sitting on the transition seating support can transfer to the toilet assembly and vice versa.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/864,095, filed on Sep. 24, 2015, which is a continuation ofInternational Application No. PCT/EP2014/056077, filed Mar. 26, 2014,published in English, which claims priority from European PatentApplication no. EP 13161103.0 filed Mar. 26, 2013, all of which areincorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to lavatories on-board a vehicle, andrelates in particular to a lavatory unit for use by persons with reducedmobility on-board a vehicle, an aircraft, a use of a lavatory unit, anda method for providing a handicapped-accessible lavatory unit on-board avehicle.

BACKGROUND OF THE INVENTION

Vehicles for longer travel durations are regularly equipped withlavatory units. For example, aircrafts are provided with lavatory unitsto provide respective service to passengers. Further examples forlavatory units on-board a vehicle, i.e. vehicles equipped with lavatoryunits are trains and also coaches. Of course, also ships may be equippedwith lavatory units. In particular aircrafts, such as airplanes orhelicopters, as well as trains and coaches have space-savingrequirements for cabin layout and for all service units to be integratedin the vehicle, because, among other reasons, the space used for serviceunits, such as lavatory units, can no longer be used for providingpassenger seats. Thus, lavatory units for use on-board a vehicle shouldbe as small as possible. However, small lavatory units with minimizedspace relations may not allow to be used by persons with reducedmobility, for example by persons sitting in a wheelchair. Therefore, atleast a selection of lavatory units on-board a vehicle must alsoconsider the specific requirements resulting from the use by personssitting in wheelchairs. For example, WO 2011/101385 A2 describes atoilet assembly for a means of transportation, for example an aircraft.A partition between two adjoining toilet spaces is movably mounted anddesigned to be moved into an open position, in which a separationbetween the two toilet spaces is eliminated. In this way, two relativelysmall toilet spaces can be converted into a larger toilet space, whichis suitable for use by persons having limited mobility, for example aperson sitting in a wheelchair. However, this solution requires inminimum two toilet spaces at a common location for providing a toiletspace that can be used by a person with reduced mobility.

BRIEF SUMMARY OF THE INVENTION

There may be a need to provide a lavatory unit on-board a vehicle thatconsiders the above-mentioned space-saving requirements, i.e. thatrequires only a minimized space, while nevertheless allowing the use bya person with reduced mobility, such as person sitting in a wheelchair.

It should be noted that the following described aspects of the inventionapply also for the lavatory unit for use by persons with reducedmobility on-board a vehicle, for the aircraft, for the use of a lavatoryunit, and for the method for providing a handicapped-accessible lavatoryunit on-board a vehicle.

According to the present invention, a lavatory unit for use by personswith reduced mobility on-board a vehicle is provided. The lavatory unitcomprises a lavatory housing structure enclosing a lavatory interiorspace, a door opening in the lavatory housing structure, a toiletassembly inside the lavatory interior space, and a transition seatingsupport for a user. The transition seating support provides a firsttransfer position and a second transfer position. In the first transferposition, in an open door state the transition seating support isdirectly accessible for a person sitting in a wheelchair that is locatedat least partly outside the lavatory unit such that the person cantransfer to the transition seating support and vice versa. In the secondtransfer position, a person sitting on the transition seating supportcan transfer to the toilet assembly and vice versa.

According to an example, in the second transition position, thetransition seating support is provided in close vicinity to a sittingsupport of the toilet assembly such that during a transition, a personis permanently supported in a tilt-free manner. The toilet sittingsupport is also referred to as toilet seat.

The term “tilt-free” relates to a support surface below an area of morethan half of the person's backside or bottom. In other words, withregards to a usual upright sitting position, a person is held by aresulting support surface below the person's centre of gravity.

In an example, the wheelchair is located outside the lavatory.

According to an example, in the second transition position, a distanceD₁ of less than approximately 15 cm between the transition seatingsupport and a sitting support of the toilet assembly is provided.

For example the distance has a maximum of a hand's width.

According to an example, the transition seating support is temporarilyarrangeable in a moving area of the toilet assembly. Upon transition tothe toilet assembly, the transition seating support is removable outsidethe moving area of the toilet assembly.

The term “moving area of the toilet assembly” relates to an area aroundthe toilet that is used for a normal course moving of a person using thetoilet. The moving area comprises in particular a region in from of thetoilet, i.e. in front of the toilet seat above a toilet bowl, e.g. thetoilet seat resting on the toilet bowl, and also on the side of the seatfor arranging the user's legs when sitting on the toilet seat. Forexample, a moving area having a distance of about 65 cm from the rearedge of a toilet seat is provided, wherein the rear edge refers to alocation in which the user's back is provided with its rear face. Theknees are then protruding into the moving area, of course depending onthe user's sitting position on the toilet seat.

In an example, the transition seating support is a tip-up seat that ispivotable upwards for storing purpose, in which the seat surface isarranged vertically.

According to an example, a knee abutment and guiding arrangement isprovided opposite the transition seating support. The knee abutment andguiding arrangement comprises a concave knee abutment recess.

The term “knee abutment surface” relates to a surface against which theuser can put his knee during the transfer procedure. Hence, the user issupported and it is prevented that the user slides off the transitionseating support.

In an example, a lateral protrusion or projection for lateral supportfor knees arranged in a vicinity of the concave abutment recess isprovided for improved guidance.

The knee abutment surface provides lateral support in both sidewardsdirections.

In an example, a washbasin is provided in the lavatory interior spaceopposite the transition seating support; and the knee abutment andguiding arrangement is provided below the washbasin.

In an example, the knee abutment recess is arranged aligned with acentre axis of the washbasin.

In an example, the knee abutment recess is arranged aligned with acentre axis of the transition seating support.

In a further example, the washbasin and the transition seating supportare aligned with their centre axes.

The term “concave shape” relates to a surface with a recess having asmooth contour to be able to act as a knee support. In an example, theconcave shape has a minimum radius of about 20 cm and a maximum radiusof about 80 cm.

According to an example, the concave abutment recess is provided with aconcave shape in a horizontal direction and a concave shape in avertical direction.

In an example, support is provided for the knees in a lateral and in avertical direction, in particular for a vertical direction in a downwarddirection.

According to an example, the concave abutment recess provides a point ofrotation or pivot axis for front tips of a knee of a person transferringfrom a wheelchair located outside the lavatory unit via the transitionseating support to the toilet assembly.

According to an example, the transition seating support is at leastarrangeable in the first transfer position and the second transferposition.

According to the present invention, a lavatory unit for use by personswith reduced mobility on-board a vehicle is provided. The lavatory unitcomprises a lavatory housing structure enclosing a lavatory interiorspace, a door opening in the lavatory housing structure, a toiletassembly inside the lavatory interior space, and a transition seatingsupport for a user. The transition seating is at least arrangeable in afirst transfer position and a second transfer position. In the firsttransfer position, in an open door state the transition seating supportis directly accessible for a person sitting in a wheelchair that islocated outside the lavatory unit such that the person can transfer tothe transition seating support and vice versa. In the second transferposition, a person sitting on the transition seating support cantransfer to the toilet assembly and vice versa.

The term “vice versa” relates to the transfer of the person in the otherdirection, i.e. from the toilet assembly to the transition seatingsupport, and from the transition seating support to the wheelchair.

This provides the advantage that the space inside the lavatory unit canactually be provided rather small, since, for example, the wheelchairstays outside the lavatory unit, respectively the lavatory interiorspace. The transition seating support allows and facilitates atransition from the wheelchair to the toilet assembly by providingso-to-speak an intermediate safe position for the person with reducedmobility. The person in a wheelchair can approach the lavatory unit,lock the wheelchair, i.e. safely stop the wheelchair, and then transferto the transition seating support for achieving a transfer positioninside the lavatory interior space. The door can then be closed, and theperson with reduced mobility can prepare, or can get prepared, for thentransferring to the toilet assembly from the transition seating support.After using the toilet assembly, the person with reduced mobility canthen transfer back to the transition seating support, and from there tothe wheelchair that is located outside the lavatory unit. For example,in case of a narrow aisle where a wheelchair cannot be turned, i.e. thewheelchair cannot be rotated about 90° to enter a toilet room, theinvention provides nevertheless access to the lavatory, because thewheelchair can stay in the aisle. The requirements for handicappedpersons for entering a lavatory are fulfilled by the transition seatingsupport. It should be noted that, besides the actual transfer to thetoilet, in which transfer the transition seating support acts as anintermediate support, the transition seating support can also be usedfor other purposes by the person with reduced mobility, for example forusing the wash-basin, e.g. for washing hands, or cosmetic procedures.

The concept of the transition seating support can be provided especiallyfor 37-inch lavatory spaces, for example.

The transition seating support can be implemented in different types oflavatories, and is also applicable to retrofit solutions. Depending onthe lavatory wall, strengthening support may be installed for retrofitsolutions.

The vehicle may preferably be an aircraft, such as an airplane orairship. The vehicle may also be a train, ship or coach.

The lavatory housing structure at least party encloses the lavatoryinterior space. For example, the lavatory housing structure encloses thelavatory interior space on all sides. The bottom enclosure may beprovided by a cabin floor structure, and the upper enclosure may beprovided by a cabin ceiling panel structure. In one example, a cabinside-wall panel structure encloses the lavatory interior space on oneside, e.g. opposite the door opening.

The person sitting in the wheelchair may be a handicapped person. Ahandicapped person is also referred to as a person with reduced mobility(PRM). The term “handicapped” relates to people with difficulties intheir walking and standing capabilities. For example, handicapped mayrelate to paralysis, blindness or reduced sight or vision, tremor orother limitations related with age, or muscle or bone diseases. In thecontext of the preset application, the term “handicapped” also comprisesreduced movement capability and the like due to pregnancy. The term“handicapped” also comprises weakness related limitations. The term“handicapped” also relates to people with disabilities.

Accessible lavatories, while modified for the needs of passengers withdisabilities, can be used by all passengers. The underlying presumptionis that the purpose of the accessible lavatory design is to enable adultpassengers to access and use a lavatory with the aid of using anon-board wheelchair. In an example, a handicapped accessible lavatory isprovided. In an example, the lavatory unit is a non-wheelchairaccessible lavatory, i.e. a wheelchair cannot enter the lavatoryinterior space.

The term “accessible” refers to a person sitting in the wheelchair canmove over to the transition seating support without the need to get intoan upright standing position. The “moving over” of the user is providedby moving from a seat-surface of the wheelchair to a seat-surface of thetransition seating support.

The term “lavatory” refers to the total enclosure of a toilet room,rather than a washbasin or sink. Lavatory is synonymous with restroom orwashroom. For example, the term lavatory is used in aviation industry todescribe the toilet enclosure. The “toilet” is the actual device towhich a person transfers to for hygienic functions. It is also referredto as commode, or water closet.

A “toilet compartment” is thus a facility customarily used by passengersfor their hygienic functions and appearance needs. According to thepresent invention, an “accessible lavatory” includes the complete toiletcompartment. The term “toilet enclosure” refers to an auxiliary areathat may be needed, and that may be contiguous to the lavatory, that canbe separated from the passenger cabin so as to provide an extended areafor privacy and maneuverability for passengers with disabilities. Thetoilet enclosure should provide the equivalent level of privacy as aregular lavatory door.

The wheelchair may be an on-board wheelchair. An “on-board wheelchair”is a wheelchair specifically designed for the use on-board a vehicle.The on-board wheelchair must be selected with access and transfer methodin mind. An on-board wheelchair does not necessarily provide the fullspectrum of a wheel-chair for normal every-day use. The on-boardwheelchair includes footrests, folding armrests that are movable orremovable, adequate occupant restraint systems, a backrest height thatpermits assistance to passengers in transferring, structurally soundhandles for maneuvering the occupied chair, and wheel locks or anotheradequate means to prevent chair movement during transfer to thetransition seating support or during turbulence. The on-board wheelchairshould be approximately the same height as the aircraft seat, and toiletseat.

The design and performance characteristics of the on-board wheelchairare integral to the level of accessibility afforded by an on-boardaccessible lavatory. Research has shown that the toilet seat andon-board wheelchair seat should be less than approximately 0.5 inches(12.8 mm) different in height to prevent injury to the transferor andtransferee during dependent transfers inside the lavatory enclosure. Insome cases the transfer from the aircraft seat to the on-boardwheelchair is a two person dependent transfer, and one or more of thetransferors may be an airline employee. In addition, the on-boardwheelchair should permit assistance to be provided both at the front andrear of the chair, so that the wheelchair can be guided down the aisleof the aircraft to the accessible lavatory. The on-board wheelchairshould permit the brakes to be applied from both the front and the backof the wheelchair, and also independently by someone performing anindependent transfer. The on-board wheelchair casters should pivot tominimize the distance required for a chair occupied by a 95 percentilemale to perform a 90° or right angle approach.

The term “transfer” relates to physical movement of a passenger betweena passenger seat, and an on-board wheelchair, and/or a lavatory toiletseat, i.e. in and out of a wheelchair, or on and off of a toilet. Theterm “independent transfer” relates to a transfer of passengers usingappropriate hand bars, hand grips, and platforms. These people do notrequire any assistance either in transfers or within the enclosed toiletcompartment. The term “dependent transfer” relates to a transfer ofpassengers who require physical assistance from another person toperform the transfer. For passengers in this category, a variety oftechniques may be used to lift the passengers clear off one seat, movethem until they are over the other seat, i.e. the transition seatingsupport, and then lower the passengers into a seated position.

A passenger's rotation during transfer is expressed in terms of “degrees(°) of transfer,” e.g., in an, up to, 90° transfer, a passenger ispivoted through, up to, an approximately 90° arc. In a side by side orlateral transfer (0°), a passenger transfers across from seat to seat.It must be noted that there are a wide variety of transfer techniquesand toileting methods, each with their own spatial requirements. Thespace required for 0° up to 90° transfers of a 95 percent male with apersonal attendant who is also a 95 percent male should accommodate theneeds of most other passengers with disabilities who use transfertechniques different from those described herein, and whose method ofusing the toilet may not require transfer, or who use mobility aids. Ithas been noted that aircraft are designed for the 95 percentile male.

The term “95 percent male” is used as definition in the field ofanthropometry, i.e. measurements of human individuals. The “95 percentmale” is also referred to as 95^(th) percentile and relates to bodymeasurements of individuals where only 5% are larger, i.e. 95% staywithin the measurements/figures. The exact figures can be taken from,for example, standard definitions such as in the NASA standard 3000T orother norms, for example EN ISO 7250 or DIN 33402.

The fundamental principles for recommendations are that the accessiblelavatory must permit a lateral (0°) or up to an approximately 90°dependent transfers of a 95 percentile male by a 95 percentile male inan enclosed lavatory space.

In an example, a transfer rotation of a handicapped person is limited toapproximately 90° for each transition or transfer step.

The transition seating support allows the seating of a handicappedperson from a wheelchair onto a toilet by two maximal approximately 90°transfer steps or transfer movements, i.e. approximately 90° from thewheelchair to the transition seating support, and approximately 90°, orless, from the transition seating support to the toilet assembly. Thesecond transfer can be provided with approximately 45° in case of arotated arrangement of the toilet assembly with relation to the lavatoryunit.

It should be noted that lateral transfer designs are recommended. Alateral transfer minimizes the “exposure time” during a transfer.Exposure time is the time a person would be at risk to falling or beingdropped. In a lateral transfer, the person has either the on-boardwheelchair, the transition seating support or the toilet directly underthem at all times, in a 90° transfer there is open space between the twoseating surfaces, e.g. the wheelchair and the next seating surface.Lateral transfers are also preferred by people who perform independenttransfers. In some instances an in-between angle for the transfer may beappropriate.

The terms “horizontal” and “vertical” relate to situations of normaloperation when the vehicle is arranged in a horizontal manner.

In an example, a washbasin is provided inside the lavatory unit. In anexample, the transition seating support provides a seating position forthe user, in which the user sits in front of a washbasin provided insidethe lavatory unit.

In an example, the transition seating support is provided as a stowableseat. The transition seating support may be provided as a tip-up seat.In one example, the transition seating support is provided as a fixedtip-up seat. In another example, the transition seating support isprovided as a horizontally sliding tip-up seat. In another example, thetransition seating support is provided as a powered sliding tip-up seat.

The tip-up seat may also be referred to as a foldable seat. Thetransition seating support comprises a seat panel supported by a hinge.The seat panel is movable between a resting position, in which the seatpanel is hanging downwards, and a transition supporting position, inwhich the seat panel is arranged approximately horizontally. In thetransition supporting position, support means may be arranged below theseat panel.

In an example, a fixation device for releasably securing a wheelchair isprovided on or in the vicinity of a door frame portion of the dooropening.

According to an example, the transition seating support is at leastarrangeable in the first transfer position and the second transferposition.

According to an example, the transition seating support is a movableseat translatable in a horizontal direction between a position closer tothe wheelchair and a position closer to the toilet assembly.

The translation between the first and second position may be providedmanually, for example by the user himself or by an assisting person. Thetranslation between the first and second position may be supported by anactuating mechanism. The translation between the first and secondposition may be provided by a controllable actuating mechanism.

In an example, the movable seat comprises actuation means for thetranslation between the first and the second position. The actuatingmeans may comprise a spindle drive, for example with a shaft joint motorfixed on a tip-up seat or a rail. Switching means can be provided forcontrol of the translation movement of the seat.

Of course, different types of handles or bars may be provided inside thelavatory unit.

According to an example, in the first the transfer position, thetransition seating support is arranged inside the lavatory interiorspace between the toilet assembly and the door opening. The transitionseating support is extending at least partly into the door opening. Thetransition seating support is accessible for the person sitting in awheelchair that is located in front of the door opening.

This provides the advantage that the person sitting in a wheelchair canapproach the lavatory unit with the wheelchair such that the wheelchairstays in front of the lavatory unit's opening. The person sitting in awheelchair can then transfer to the transition seating support that isarranged inside the lavatory interior space, but provided in the dooropening to allow a direct transfer from the wheelchair onto thetransition seating support, thus providing enhanced security for thehandicapped person, for example.

The term “extending at least partly into the door opening” refers to anarrangement where the seat surface of the transition seating support isaccessible for a user from the outside, i.e. the user can directly takeplace on the transition seating support without the need to first enterthe lavatory. In the seated state, the user is located inside thelavatory unit.

In an example, the transition seating support is provided in a fixedmanner, and the first transfer position and the second transfer positionrelate to the same transfer position.

In another example, the transition seating support is provided movableat least between the first transfer position and the second transferposition.

According to an example, in the first transfer position, the transitionseating support is arranged at least partly outside the lavatoryinterior space. The transition seating support is movable at leastbetween the first transfer position and the second transfer position.

This provides the advantage that the person sitting in a wheelchair candirectly access the transition seating support in the space outside thelavatory interior space, for example allowing an easier transition fromthe wheelchair to the transition seating support. The transition seatingsupport is then moved, together with the person with reduced mobility,to the interior space of the lavatory unit, for example to close thedoors and to further provide transition from the transition seatingsupport to the toilet assembly.

In an example, the transition seating support is a movable seattranslatable in a horizontal direction between a position closer to thedoor opening and a position closer to the toilet assembly.

According to an example, the transition seating support is movable atleast partly underneath a seating support of an on-board wheelchair forfacilitating a transfer from the wheelchair to the transition seatingsupport.

For example, the on-board wheelchair is provided with a matching seatingsupport construction to allow the positioning of the transition seatingsupport at least partly underneath, and then a so-to-speak dropdown fromthe seating support of the on-board wheelchair to the transition seatingsupport, thus facilitating the transfer from the wheelchair to thetransition seating support.

According to an example, the transition seating support is movable atleast partly over the toilet assembly.

This provides the advantage that the transition situation for thetransfer from the transition seating support to the toilet assembly isfurther improved by, for example, a partly overlapping of the transitionseating support and the toilet assembly, for example the transitionseat.

For example, the transition seating support is slideable over the toiletassembly such that the user can rest on the transition seating supportin case he/she does not want to use the toilet, but wants to use thelavatory for other purposes, for example for using the wash-basin.

In an example, the transition seating support can be brought into aposition completely arranged over the toilet assembly. In anotherexample, the transition seating support covers only a part of the toiletassembly.

According to an example, a transition seat extension is provided atleast temporarily between the transition seating support and a toiletseat of the toilet assembly.

The transition seat extension may be a slideable extension attached tothe transition seating support.

The transition seat extension may be an extension element pivotablemounted to the inside surface of the lavatory housing structure.

The transition seat extension provides the advantage to allow a closermovement of the person with reduced mobility towards the toilet assemblyto then further facilitate the transfer to the toilet assembly, i.e. atoilet seat. Of course, similar is the case for the transition from thetoilet assembly to the transition seating support and from thetransition seating support onto the wheelchair.

According to an example, the transition seating support comprises asitting surface comprises two upper-leg resting segments extending froma bottom resting segment. A cut-out is provided between the twoupper-leg resting segments for leg positioning of an assisting person.

This provides the advantage that in case assisting persons are needed,the assisting person, for example holding and lifting the handicappedperson to or from the wheelchair, can approach the person with reducedmobility closer, such that the lifting is facilitated.

According to an example, the transition seating support is attached toan inner side of a portion of the lavatory housing structure, on whichouter side a cabin attendant seat is provided. The cabin attendant seatand the transition seating support are provided by a bi-functionalseating support.

This provides the advantage that the same seat can be used for twodifferent purposes, i.e. two different functions. This allowsweight-saving and also generates synergetic effects, leading also tocost benefits and the like.

In an example, guiding means and a slot opening are provided in thelavatory housing structure. A seating element is slideable between afirst position and a second position. In the first position, the seatingelement is arranged outside the lavatory housing, the seating elementacting as the cabin attendant seat (CAS). In the second position, theseating element is arranged inside the lavatory housing, the seatingelement acting as the transition seating support.

The guiding means may be provided as a rail system for slidinglysupporting the seating element. The slot opening may be provided as acut-out in the lavatory housing structure.

In an example, a cut-out and rotating support means for a seat areprovided in the lavatory housing structure. In an option i), the seat ismounted rotatably around a vertical axis between a first rotationposition and a second rotation position. In the first rotation position,the seat is facing to a cabin space, the seat acting as the cabinattendant seat. In the second rotation position the seat is facing thelavatory interior space, the seat acting as the transition seatingsupport. In an option ii), the seat is mounted rotatably around ahorizontal axis between a first rotation position and a second rotationposition. In the first rotation position, the seat is facing to a cabinspace, the seat acting as the cabin attendant seat. In the secondrotation position, the seat is facing the lavatory interior space, theseat acting as the transition seating support.

In the first case i), the seat is provided with a first and second seatpanel. The first seat panel is a seat surface, and the second seat panelis a backrest. The seat panel can be folded parallel to the second seatpanel for rotating between the first and second rotation position.

In the second case ii), the seat is provided with a first and a secondseat panel. In the first position, the first seat panel is arranged asseat surface, and the second seat panel is provided as backrest, whereasin the second position, the second seat panel is arranged as the seatsurface and the first seat panel is provided as backrest.

The toilet assembly may be provided with an inclined angle to a sidewallof the lavatory housing structure. For example, the toilet assembly,i.e. the toilet itself, is provided in an angle of 10° to 80°, forexample 30° to 60°, or in a further example, approximately 45°.

According to the present invention, also an aircraft with a fuselagestructure enclosing a cabin space and at least one lavatory unit isprovided. At least one lavatory unit is provided as a lavatory unitaccording to one of the above-mentioned examples.

In an example, the aircraft has at least one door in the fuselagestructure. The cabin comprises a door exit/entry area adjacent to thedoor, and a lavatory unit next to the exit/entry area is providedaccording to one of the examples above. The lavatory unit according tothe present invention is preferably arranged next to a forward door on aportside of the aircraft. The forward door on the portside of theaircraft is also referred to as door A. Of course, also lavatories atother locations throughout the aircraft can be provided.

According to the present invention, also the use of a lavatory unitaccording to one of the above-mentioned examples in an aircraft with afuselage structure enclosing a cabin space is provided.

According to the present invention, a method is provided for providing ahandicapped accessible lavatory unit on-board a vehicle, comprising thefollowing steps: a) providing a lavatory housing structure enclosing alavatory interior space with a toilet assembly inside, and a dooropening in the lavatory housing structure; and b) providing a transitionseating support for a user.

In an open door state, a person sitting in a wheelchair that is locatedoutside the lavatory unit can directly access the transition seatingsupport arranged in the first transfer position and for transferringfrom the wheelchair to the transition seating support and vice versa.The person sitting on the transition seating support arranged in thesecond transfer position can transfer to the toilet assembly and viceversa.

According to the present invention, the use of a lavatory unit forhandicapped persons, for example, or other persons with reducedmobility, is provided by the lavatory unit that is equipped with atransition seating support allowing and facilitating the transfer from awheelchair to the toilet assembly, i.e. the transition seat. Since thetransition seating support can be accessed by the person with reducedmobility while being outside the lavatory unit, the need to provideadditional space inside the lavatory unit for parking the wheelchair isomitted. Rather, the space outside the lavatory unit, e.g. the floorspace of an aisle, is temporarily used for storing the wheelchair. Thus,although the lavatory unit itself is provided with minimized dimensions,the usable space available for the use by a person with reducedmobility, for example sitting in a wheelchair, is enlarged. Theso-to-speak connecting element between the inside and the outside, i.e.the region where a wheelchair can be parked outside the lavatory unitand the toilet inside the lavatory unit, is provided by arranging thetransition seating support.

These and other aspects of the present invention will become apparentfrom and be elucidated with reference to the embodiments describedhereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will be described in thefollowing with reference to the following drawings:

FIG. 1 shows a schematic plan view of an example of a lavatory unit;

FIG. 2 shows a schematic plan view of another example of a lavatoryunit;

FIG. 3 shows a schematic plan view of a further example of a lavatoryunit;

FIG. 4a shows a schematic plan view of a still further example of alavatory unit;

FIG. 4b shows a plan view of the example of FIG. 4a in view plane abovea washbasin;

FIG. 4c shows a perspective of the example of FIGS. 4a and 4b with apassenger located on a transition seating support inside a lavatoryinterior space;

FIG. 4d shows a plan view of the example of FIGS. 4a, 4b and 4c with apassenger indicated in different positions during transfer from awheelchair onto a toilet assembly;

FIG. 5 shows a schematic plan view of an example of a lavatory unit;

FIG. 6 shows a plan view of a further example of a lavatory unit;

FIG. 7a shows a further example of a lavatory unit;

FIG. 7b shows yet another example of a lavatory unit;

FIG. 8 shows a further example of a lavatory unit with a transitionseating support that can be arranged at least partly outside thelavatory unit;

FIG. 9 shows an example of a lavatory unit with a transition seatingsupport arranged inside the lavatory interior space.

FIG. 10 shows an example of a lavatory unit in relation with threedifferent stages of use in relation with an assisting person;

FIG. 11 shows an example of a transition seating support;

FIG. 12 schematically shows a vertical section of an example of atransition seating support;

FIG. 13a shows a further example of a transition seating support in aplan view;

FIG. 13b shows a schematic elevation of the transition seating supportof FIG. 13 a;

FIG. 14a shows a further example of a lavatory unit with a transitionseating support in a plan view;

FIG. 14b shows the transition seating support of FIG. 14a in anelevation view;

FIG. 15a shows an example of a cabin attendant seat and transitionseating support as a bi-functional seating support in a perspectiveview;

FIG. 15b shows the bi-functional seating support of FIG. 15a in a planview;

FIG. 16a shows a further example of a bi-functional seating support witha vertical rotating axis in a perspective view;

FIG. 16b shows the bi-functional seating support of FIG. 16a in a planview;

FIG. 17a shows a further example of a bi-functional seating support witha horizontal pivoting axis, in a perspective view;

FIG. 17b shows the bi-functional support of FIG. 17a in a plan view;

FIG. 18 shows an example of an aircraft in a plan view (section shownonly) with a lavatory unit; and

FIG. 19 shows an example of a method for providing ahandicapped-accessible lavatory unit on-board a vehicle.

DETAILED DESCRIPTION

FIG. 1 shows a lavatory unit 10 for use by persons with reduced mobilityvehicle. The lavatory unit 10 comprises a lavatory housing structure 12enclosing a lavatory interior space 14. Further, a door opening 16 inthe lavatory housing structure 12 is provided. Still further, a toiletassembly 18 is shown inside the lavatory interior space 14. Stillfurther, a transition seating support 20 is provided for a user. Thetransition seating support provides a first transfer position and asecond transfer position (shown in more detail below). In the firsttransfer position, in an open door state, the transition seating support20 is directly accessible for a person sitting in a wheelchair that islocated at least partly outside the lavatory unit 10 such that theperson can transfer to the transition seating support 20 and vice versa.In FIG. 1, a wheelchair 22 is shown with dotted lines. In the secondtransfer position, a person sitting on the transition seating support 20can transfer to the toilet assembly 18 and vice versa. As an example,the door opening 16 can be provided with a pivoting door element 24.However, also sliding doors, rotating doors or folding doors or doorswith rolling elements can be provided.

For example, the lavatory unit 10 may be provided as anon-wheelchair-accessible lavatory, as indicated.

In a further example, an additional curtain is provided in the corridorspace outside the lavatory such that the wheelchair is hidden from thecabin to provide at least a bit of privacy for the person transferringto the transition seating support. Upon transfer to the interior spaceof the lavatory unit, the wheelchair is moved out of the door entryopening, e.g. by a flight attendant, such that the door can be properlyclosed.

FIG. 2 shows a further example of the lavatory unit 10. A distance D₁ ofless than approximately 15 cm is provided between the transition seatingsupport and a sitting support of the toilet assembly is provided. Forexample the distance D₁ has a maximum of a hand's width.

The wheelchair 22 can approach the door entry opening in an obliquemanner, e.g. diagonally. A first dotted line 11 indicates a longitudinalaxis of the wheelchair 22. A second dotted line 13 indicates a centreaxis of the transition seating support 20. A third dotted line 15indicates an axis to a position in the middle of the toilet assembly 18.The transfer to the transition seating support 20 is provided in anangle α₁ of about 45°. The transfer from the transition seating support20 to the middle of the toilet assembly 18 is provided in an angle α₂ ofabout 45°.

FIG. 3 shows a still further example of the lavatory unit 10. As anoption, a washbasin 17 is indicated. The transition seating support 20is temporarily arrangeable in a moving area 19 of the toilet assembly.The transition seating support 20 is removable outside the moving areaof the toilet assembly, e.g. upon transition to the toilet assembly.This is indicated with a dotted line 21. As an example, the transitionseating support 20 is provided as a tip-up seat.

FIG. 4a shows another example of the lavatory unit 10, according towhich a knee abutment and guiding arrangement 23 is provided oppositethe transition seating support 20. The knee abutment and guidingarrangement 23 comprises a concave knee abutment recess 25. In order toensure a sufficient support and guidance, a minimum distance ofapproximately 55 cm, and a maximum distance of approximately 75 cm isprovided. In an example, a distance D₂ of about 60 to 65 cm is provided,wherein the distance is measured from the rear edge of the seatingsupport to the knee abutting surface. The rear edge is the back side ofthe seating support and usually also relates to the wall's surface, orseating backrest, against which the user can lean during use of theseating support. For example, a distance D₃ between the abutment recess25 and a front edge of the transition seating support of about 20 to 35cm is provided.

In FIG. 4b , a washbasin 27 is shown as an option, the washbasinarranged above the knee abutment and guiding arrangement 23 with theconcave knee abutment recess 25. (In the drawing of FIG. 4b , theconcave knee abutment recess 25 is not shown.) In an example, thewashbasin is aligned with the transition seating support 20. In anotherexample, the washbasin is displaced sidewards, e.g. towards the toiletassembly. In a still further example, the drainage of the washbasin isarranged in a displaced manner, e.g. towards the toilet assembly. Thiscan be provided for the aligned washbasin and also for the displacedwashbasin.

FIG. 4c shows a perspective view of a part of the lavatory interiorspace 14. A person 29 is shown arranged on the transition seatingsupport 20, e.g. during transfer to the toilet assembly 18. The personis shown with upper legs 31 extending towards the part below thewashbasin 27. The legs 31 are arranged with knees 33 in the vicinity ofthe concave knee abutment recess 25 of the knee abutment and guidingarrangement 23. Thus, guiding support for the person 29 is provided.

FIG. 4d shows an overview of different positions of a person 35 duringtransfer from the wheelchair 22 to the toilet assembly 18 and viceversa. In a first position P1, the person 35 is shown sitting in thewheelchair 22. In a second position P2, the person 35 is shown sittingon the transition seating support 20. In a third position P3, the person35 is shown sitting on the toilet assembly 18. As can be seen, the knees33 of the person 35 are arranged in the vicinity of the concave kneeabutment recess 25 during transfer. In other words, the personso-to-speak pivots around this concave knee abutment recess 25, thelatter providing support to avoid that the person, with reducedmobility, falls off the transition seating support 20.

It must be noted that aspects relating to the transfer procedure arealso described below in relation with other exemplary embodiments, suchas examples having a movable (via translation) transition seatingsupport 20. These aspects are also applicable for the exemplaryembodiments described above, such as the examples having a fixedlyarranged transition seating support 20, which may be temporarilyremovable for example via tilting upwards or downwards.

FIG. 5 shows the lavatory unit 10 comprising the lavatory housingstructure 12 enclosing the lavatory interior space 14. In the firsttransfer position, in an open door state, the transition seating support20 is directly accessible for a person sitting in the wheelchair that islocated outside the lavatory unit 10 such that the person can transferto the transition seating support 20 and vice versa. As an option, awheelchair fixation device 23 may be provided outside the lavatory unit10, for example in the vicinity of a doorframe area. As an example, thedoor opening 16 can be provided with a sliding door element 25. However,also pivoting or rotating doors or folding doors or doors with rollingelements can be provided.

For example, the lavatory unit 10 may be provided as anon-wheelchair-accessible lavatory, as indicated.

It must be noted that the wheelchair is shown in exemplary positions inrelation with the door opening of the lavatory. Of course, otherpositions (not shown) are also provided. The positioning of thewheelchair is also depending on the spatial relations of the area infront of the lavatory, i.e. where the wheelchair is temporarily parked.For example, the wheelchair is parked such that a lateral transfer tothe transition seating support is provided. In another example, thewheelchair is parked such that a 90° transfer to the transition seatingsupport is provided.

In a further example, the person transfers to the transition seatingsupport in a first position, such as transverse to the flight direction,in flight direction or against flight direction. Before transferring tothe toilet assembly, the person may change the position. For example,the person is transferring to the transition seating support from thewheelchair in a position looking away from the opening, and is laterturning on the transition seating support such that the view istransverse to the initial direction.

FIG. 6 shows an example of the lavatory unit 10 where the transitionseating support 20 is arranged at least partly outside the lavatoryinterior space in the first transfer position. In FIG. 6, the transitionseating support 20 is shown in the first transfer position, indicatedwith reference numeral 26. A double arrow 28 indicates the movability ofthe transition seating support 20. A dotted frame 30 indicates theabove-mentioned second transfer position. The transition seating support20 is thus movable at least between the first transfer position 26 andthe second transfer position 30. For example, the wheelchair 22 can bearranged next to the transition seating support 20 in the first transferposition 26.

As indicated with dotted lines in FIG. 6, the lavatory unit 10 may beequipped with a wash-basin 32, arranged in relation with a horizontalsurface 34. It must be noted that the provision of the wash-basin 32 isshown as an option in FIG. 6, but is also provided as an option forother embodiments of the other figures.

It must be noted that the illustrations only indicate the narrow spatialrelations that may be provided in a lavatory unit for on-board anaircraft without showing the spatial relations in scale. For example, ina transfer position on the transition seating support, the person maynearly touch an opposing wall, for example, a base structure or lowerwall of a wash-basin arrangement.

FIG. 7A shows a further example, where the transition seating support 20is a movable seat 36 translatable in a horizontal direction, asindicated with a double arrow 38, between a position closer to thewheelchair 22 and a position closer to the toilet assembly 18.

In a further example, not shown, the movable transition seating support20 is provided in combination with the examples of FIGS. 1 to 4, and inparticular with the concave knee abutment recess 25. The latter providesadditional support during the transfer from the movable transition seatextension 20 to the toilet assembly 18.

For example, the transition seating support 20 is arranged inside thelavatory interior space in the first transfer position, indicated withthe reference numeral 26. The transition seating support 20 is arrangedcloser to the door opening. A dotted frame indicates the second transferposition 30, into which the transition seating support 20 can be moved.

As an example, an assisting person 40 is shown in FIG. 7A, for assistingthe transfer of a handicapped person 42 from the wheelchair 22 to thetransition seating support 20.

Further, it must be noted that the toilet assembly 18 is shown in aslightly inclined manner, i.e. in an angle, i.e. rotated towards thetransition seating support 20 for further facilitating the transfer fromthe handicapped person 42 via the transition seating support 20 to thetoilet assembly 18. It must be noted that this shown as an option, i.e.the feature of the inclined arranged toilet can also be omitted. It mustbe noted further, that the inclined toilet arrangement is also providedfor the other embodiments of the other figures and described in moredetail below and above.

Further, the surrounding of the lavatory unit 10, for example in anaircraft is indicated: A first line 44 indicates an interior wall of agalley provided opposite the lavatory unit 10 on the other side of anail area 46. An arrow 48 indicates an access to an adjoining cockpitarea. Further, a second line 50 indicates a separation from a door entryarea 52, the door shown with a double line 54 for simplicity, from acabin space arranged to the right. Further, a curtain, or otherseparating component/element 56 can be provided for separation from thecabin space.

The space outside the lavatory interior space, e.g. the adjacent aislespace and the door entry/exit area thus form a toilet enclosure.

FIG. 7B shows a further example indicating different stages during thetransition procedures, which shall be described in the following withthe general principle steps. First, the lavatory door is open. Next, thetransition seating support 20 is prepared (see also below). Thewheelchair 22 is positioned next to the lavatory door opening 16. As anoption, the curtain 56 can be closed to provide a visual protection forthe person with reduced mobility for passengers' direct view located inthe cabin, not further shown. The person with reduced mobility, i.e. thehandicapped person 42 is then positioned on the transition seatingsupport 20, for example with the help and support of the assistingperson 40. Next, the transition seating support 20 is moved from thefirst transfer position 26 to the second transfer position 30, asindicated with a first arrow 58. Next, the handicapped person 42 can betransferred to the toilet assembly 18, as indicated with a second arrow60. For example, the assisting person 40 can also provide support forpreparing the handicapped person 42 for the use of the toilet assembly18.

FIG. 8 shows a further example, where the transition seating support 20is moveable at least partly underneath a seating support 62 of anon-board wheelchair or other wheelchair, as indicated with the dottedwheelchair 22, for facilitating a transfer from the wheelchair 22 to thetransition seating support 20. An arrow 64 indicates the movabilitybetween the first transfer position 26 and the second transfer position30.

FIG. 9 shows a further example, where the transition seating support 20is movable at least partly over the toilet assembly 18, as indicatedwith double arrow 66. The position, in which the transition seatingsupport 20 is moved partly or completely over the toilet assembly 18, isindicated with a dotted frame 68.

According to a further example, shown in FIG. 10, a transition seatextension 70 is provided at least temporarily between the transitionseating support 20 and a toilet seat (not shown in detail) of the toiletassembly 18. The transition seat extension 70 further supports thetransfer movement, which can be supported by the assisting person 40, asindicated. The intermediate step provided by the transition seatextension 70 is indicated with an arrow 72 in addition to the firstarrow 58 for the first transfer from the wheelchair to the transitionseating support 20, and the second arrow 60 indicating the transfer tothe toilet assembly 18.

In a further example, not shown, the transition seat extension 70 isprovided in combination with the examples of FIGS. 1 to 4, e.g. theconcave knee abutment recess 25.

The transition seat extension may be provided movable to servetemporally as additional support. In another example, the transitionseat extension is fixedly installed.

However, it must be noted that the assisting person 40 is shown in thefigures as an option only. Of course, also the self-supported transferof the handicapped person 42 or other person with reduced mobility froma wheelchair, for example, may also be provided.

FIG. 11 shows a detail of an example of the transition seating support20, comprising a sitting surface 74 comprises two upper-leg restingsegments 76 extending from a bottom resting segment 78. A cut-out 80 isprovided between the two upper-leg resting segments 76 for legpositioning of an assisting person, as indicated with the assistingperson 40. Thus, the handling comfort for the person with reducedmobility is increased and the positioning procedure for assistant isprovided in an optimized ergonomic way.

The transition seating support 20 may be provided as a storable seat 82,as indicated in FIG. 12, illustrating a folded-up state 84 in the lowerhalf and a folded-away state 86 in the upper half. A seating surface 88may be attached to a wall of the cabin structure 90 via a hinge element92. The resulting up-folding movement is indicated with an arrow 94. Asupport structure 96, only schematically shown, can temporarily beprovided to ensure proper stability. In another example, the seat issuspended by a suspending support arrangement. Of course, also othermechanisms for load bearing are provided. One or several supportelements may be provided. Of course, also a seating support that can befolded down for the opened use state can be provided. In a furtherexample, also not shown, the transition seating support 20 is providedas a fixed seating support.

For example, the transition seating support 20 is provided as ahorizontally sliding transition seating support, as indicated with anarrow 98 in FIG. 13A. For example, three different positions can bepreset in a sliding mechanism 102, also shown in FIG. 13B. The differentpositions 100 are indicated with three circles with different numeralsinside. Of course, also adjustability in a horizontal and a verticaldirection can be provided, as indicated with double arrow 104.

The horizontally sliding seating support can be provided as ahorizontally sliding tip-up seat, or fold-up or fold-down seat, or alsoas a fixed seat in a horizontally sliding mechanism.

In another example, shown in FIG. 14A and FIG. 14B, the transitionseating support 20 is provided as a powered sliding seat 106, providinga transition movement, indicated with double arrow 108. The powered seatcan also be provided as a power tip-up, fold-down or fold-up seat, or asa fixed seat being slideable by a drive mechanism. For example, a drivemechanism 110 is attached to the seating support 106. In anotherexample, a drive mechanism 112 is provided attached to a wall structure,for example also connected to a rail or the wall. For activating thedrive mechanism, a switch 114 can be provided in the vicinity of thetransition seating support 20.

For example, a spindle drive with shaft joint can be provided. Inanother example, a motor is fixed on the rail. The spindle drive withshaft joint motor can also be provided fixed on the seat, for examplethe tip-up seat.

In a further example, not shown, the transition seating support 20 ofFIGS. 12 to 14B is provided in combination with the examples of FIGS. 1to 4, e.g. in particular with the provision of the transition seatingsupport 20 in the moving area relating to the use of the toilet assemblyand with the concave knee abutment recess 25.

In a further example, the transition seating support 20 is attached toan inner side 114 of a portion of the lavatory housing structure 12, onwhich outer side a cabin attendant seat 116 is provided. The cabinattendant seat and the transition seating support 20 are provided by abi-functional seating support 118, which shall be described in thefollowing with three different examples. The cabin attendant seat 116 isa seat element for cabin attendant staff members that is used duringtakeoff and landing phases, and that is not used, for example, duringembarkation and disembarkation of the passengers, for example becausethe seat is located in a door entry/exit area. The cabin attendant seatmay be equipped with seatbelts for the cabin attendant staff member. Forexample, the cabin attendant seat is also not used during the flightphase of the aircraft, in which flight phase, passengers are allowed tomove on-board the aircraft, and for example to use the lavatory unit.

FIG. 15 shows a perspective view in FIG. 15A and a plan view in FIG.15B, indicating a seating element 120 that is slideable between a firstposition 122 and a second position 124. In the first position 122, theseating element is arranged outside the lavatory housing, i.e. thelavatory unit 10, the seating element acting as the cabin attendant seat116. In the second position 124, the seating element 120 is arrangedinside the lavatory housing structure 12, the seating element acting asthe transition seating support 20. The lavatory housing structure 12 isprovided with guiding means 126 (not further shown in detail) and a slotopening 128. The horizontal sliding movement to change between the twofunctions is indicated with a double arrow 130.

FIG. 16 shows another example of the bi-functional seating support 118in a perspective view in FIG. 16A and in a plan view in FIG. 16B. Acut-out 132 and rotating support means, indicated with two double arrows134, for a seat are provided in the lavatory housing structure 12. Theseat is mounted rotatably around a vertical axis 136 between a firstrotation position 138 and a second rotation position 140. In the firstrotating position 138, the seat is facing to a cabin space, i.e. outsidethe lavatory unit 10, the seat acting as the cabin attendant seat 116.In the second rotating position 140, the seat is facing the lavatoryinterior space 14, the seat acting as the transition seating support 20.A further double arrow 142 indicates the change between the twopositions by the rotation around the vertical axis 136.

A further example of the bi-functional seating support 118 is shown inFIG. 17A in a perspective view, and in FIG. 17A in a plan view. The seatis mounted rotatably around a horizontal axis 144 between a firstrotation position 146 and a second rotation position 148. In the firstrotation position 146, the seat is facing to the cabin space, i.e.outside the lavatory unit 10, the seat acting as the cabin attendantseat 116. In the second rotation position 148, the seat is facing thelavatory interior space 14, the seat acting as the transition seatingsupport 20.

FIG. 18 shows an aircraft 200 (only the front section is shownschematically) with a fuselage structure 202, enclosing a cabin space204, and at least one lavatory unit 206. At least one lavatory unit isprovided as the lavatory unit 10, according to one of theabove-mentioned examples. The aircraft 200 may be provided with dooropenings 2008 in the fuselage structure 202. The cabin 204 may comprisea door exit/entry area 210 adjacent to the door 208, and a lavatory unit10 next to the exit/entry area is provided according to one of theabove-described examples. For example, the lavatory unit 10 is arrangednext to a forward door on a portside of the aircraft, which door isindicated with reference numeral 212. The forward door in the portsideof the aircraft 200 is also referred to as door A, as indicated.

FIG. 19 shows a method 300 for providing a handicapped-accessiblelavatory unit 10 on-board a vehicle. The following steps are provided:In a first provision step 310, a lavatory housing structure enclosing alavatory interior space with a toilet assembly inside, and a dooropening in the lavatory housing structure is provided. In a secondprovision step 320, a transition seating support for a user is provided.In an open door state, a person sitting in a wheelchair that is locatedoutside the lavatory unit can directly access the transition seatingsupport arranged in the first transfer position and can transfer fromthe wheelchair to the transition seating support and vice versa. Theperson sitting on the transition seating support arranged in the secondtransfer position can transfer to the toilet assembly and vice versa.The first provision step 310 is also referred to as step a), and thesecond provision step 320 as step b).

According to further examples, not shown in detail, the method alsocomprises providing a lavatory housing structure and a transitionseating support with the above-mentioned features and characteristics.

It has to be noted that embodiments of the invention are described withreference to different subject matters. In particular, some embodimentsare described with reference to method type claims whereas otherembodiments are described with reference to the device type claims.However, a person skilled in the art will gather from the above and thefollowing description that, unless otherwise notified, in addition toany combination of features belonging to one type of subject matter alsoany combination between features relating to different subject mattersis considered to be disclosed with this application. However, allfeatures can be combined providing synergetic effects that are more thanthe simple summation of the features.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive. Theinvention is not limited to the disclosed embodiments. Other variationsto the disclosed embodiments can be understood and effected by thoseskilled in the art in practicing a claimed invention, from a study ofthe drawings, the disclosure, and the dependent claims. In the claims,the word “comprising” does not exclude other elements or steps, and theindefinite article “a” or “an” does not exclude a plurality. A singleprocessor or other unit may fulfil the functions of several itemsre-cited in the claims. The mere fact that certain measures are re-citedin mutually different dependent claims does not indicate that acombination of these measures cannot be used to advantage. Any referencesigns in the claims should not be construed as limiting the scope.

While at least one exemplary embodiment of the present invention(s) isdisclosed herein, it should be understood that modifications,substitutions and alternatives may be apparent to one of ordinary skillin the art and can be made without departing from the scope of thisdisclosure. This disclosure is intended to cover any adaptations orvariations of the exemplary embodiment(s). In addition, in thisdisclosure, the terms “comprise” or “comprising” do not exclude otherelements or steps, the terms “a” or “one” do not exclude a pluralnumber, and the term “or” means either or both. Furthermore,characteristics or steps which have been described may also be used incombination with other characteristics or steps and in any order unlessthe disclosure or context suggests otherwise. This disclosure herebyincorporates by reference the complete disclosure of any patent orapplication from which it claims benefit or priority.

The invention claimed is:
 1. A lavatory unit for use by persons withreduced mobility on-board a vehicle, the lavatory unit comprising: alavatory housing structure enclosing a lavatory interior space; a dooropening in the lavatory housing structure; a toilet assembly inside thelavatory interior space; and a transition seating support for a user;wherein the transition seating support is configured to provide a firsttransfer position and a second transfer position, wherein in the firsttransfer position, in an open door state the transition seating supportis directly accessible for a person sitting in a wheelchair located atleast partly outside the lavatory unit such that the person can transferto the transition seating support and vice versa, wherein in the secondtransfer position, a person sitting on the transition seating supportcan transfer to the toilet assembly and vice versa, wherein thetransition seating support is temporarily arrangeable in a moving areaof the toilet assembly, and wherein upon transition to the toiletassembly, the transition seating support is removable outside the movingarea of the toilet assembly, and wherein the transition seating supportis a movable seat translatable in a horizontal direction between aposition closer to the wheelchair and a position closer to the toiletassembly.
 2. The lavatory unit according to claim 1, wherein in thesecond transition position, the transition seating support is providedin close vicinity to a sitting support of the toilet assembly such thatduring a transition, a person is permanently supported in a tilt-freemanner.
 3. The lavatory unit according to claim 2, wherein in the secondtransition position, a distance D₁ of less than approximately 15 cmbetween the transition seating support and a sitting support of thetoilet assembly is provided.
 4. The lavatory unit according to claim 1,further comprising a knee abutment and guiding arrangement opposite thetransition seating support, wherein the knee abutment and guidingarrangement comprises a concave knee abutment recess.
 5. The lavatoryunit according to claim 4, wherein the concave abutment includes aconcave shape in a horizontal direction and a concave shape in avertical direction.
 6. The lavatory unit according to claim 4, whereinthe concave abutment recess provides a point of rotation for front tipsof a knee of a person transferring from a wheelchair located outside thelavatory unit via the transition seating support to the toilet assembly.7. The lavatory unit according to claim 1, wherein the transitionseating support is at least arrangeable in the first transfer positionand the second transfer position.
 8. The lavatory unit according toclaim 1, wherein in the first transfer position, the transition seatingsupport is arranged inside the lavatory interior space between thetoilet assembly and the door opening, wherein the transition seatingsupport is extending at least partly into the door opening; and whereinthe transition seating support is accessible for a person sitting in awheelchair that is located in front of the door opening.
 9. The lavatoryunit according to claim 1, wherein in the first transfer position, thetransition seating support is arranged at least partly outside thelavatory interior space, and wherein the transition seating support ismovable at least between the first transfer position and the secondtransfer position.
 10. The lavatory unit according to claim 1, whereinthe transition seating support is movable at least partly underneath aseating support of an on-board wheelchair for facilitating a transferfrom the wheelchair to the transition seating support.
 11. The lavatoryunit according to claim 1, wherein the transition seating support ismovable at least partly over the toilet assembly.
 12. The lavatory unitaccording to claim 1, wherein a transition seat extension is provided atleast temporarily between the transition seating support and a toiletseat of the toilet assembly.
 13. The lavatory unit according to claim 1,wherein the transition seating support comprises a sitting surfacecomprising two upper-leg resting segments extending from a bottomresting segment, and wherein a cut-out is provided between the twoupper-leg resting segments for leg positioning of an assisting person.14. The lavatory unit according to claim 1, wherein the transitionseating support is attached to an inner side of a portion of thelavatory housing structure, on which outer side a further cabin seat isprovided; and wherein the further cabin seat and the transition seatingsupport are provided by a bi-functional seating support.
 15. Anaircraft, comprising: a fuselage structure enclosing a cabin space; andat least one lavatory unit according to claim
 1. 16. A method forproviding a handicapped accessible lavatory unit on-board a vehicle,comprising: a) providing a lavatory housing structure enclosing alavatory interior space with a toilet assembly inside, and a dooropening in the lavatory housing structure; and b) providing a transitionseating support for a user, wherein, in an open door state, a personsitting in a wheelchair located at least partly outside the lavatoryunit can directly access the transition seating support providing afirst transfer position and can transfer from the wheelchair to thetransition seating support and ice versa; and wherein the person sittingon the transition seating support providing a second transfer positioncan transfer to the toilet assembly and vice versa, wherein thetransition seating support is temporarily arrangeable in a moving areaof the toilet assembly; and wherein upon transition to the toiletassembly, the transition seating support is removable outside the movingarea of the toilet assembly, and wherein the transition seating supportis a movable seat translatable in a horizontal direction between aposition closer to the wheelchair and a position closer to the toiletassembly.
 17. A lavatory unit for use by persons with reduced mobilityon-board a vehicle, the lavatory unit comprising: a lavatory housingstructure enclosing a lavatory interior space; a door opening in thelavatory housing structure; a toilet assembly inside the lavatoryinterior space; and a transition seating support for a user; wherein thetransition seating support is configured to provide a first transferposition and a second transfer position; wherein in the first transferposition, in an open door state the transition seating support isdirectly accessible for a person sitting in a wheelchair located atleast partly outside the lavatory unit such that the person can transferto the transition seating support and vice versa; wherein in the secondtransfer position, a person sitting on the transition seating supportcan transfer to the toilet assembly and vice versa; and furthercomprising a knee abutment and guiding arrangement opposite thetransition seating support; wherein the knee abutment and guidingarrangement comprises a concave knee abutment recess.
 18. The lavatoryunit according to claim 16, wherein the concave abutment includes aconcave shape in a horizontal direction and a concave shape in avertical direction.
 19. The lavatory unit according to claim 16, whereinthe concave abutment recess provides a point of rotation for front tipsof a knee of a person transferring from a wheelchair located outside thelavatory unit via the transition seating support to the toilet assembly.